Grinding-cylinder for reducing wood to pulp



S. M. ALLEN Grinding Cylinder for Reducing Wood to Pulp.`

Patented `Jan. 6,1880` lCf i 17u/19%?" .f G

N. PETERS. PMaTo-UTHQGRAPMER, wAsmNGfoN. nA 2y UNITED STATES PATENT OFFICE.

STEPHEN M. ALLEN, OF DUXBURY, MASSACHUSETTS.

GRlNDlNG-CYLINDER FOR REDUCING WOOD TO PULP.

SPECIFICATION forming part of Letters Patent No. 223,304, dated January 6, 18 80.

Application filed December 11, 1879. Y

To all whom 'it may concern Be it known that I, STEPHEN M. ALLEN, of Duxbury, Massachusetts, have invented a new and useful Improvement in Grinding-Cylinders for Reducing Wood to Pulp, which invention is fully set forth in the following specilication.

In the manufacture of paperpulp I have found that for the purpose of crushing, disintegrating, and grinding wood and other fibers rollers or grinders of emery or other artiicial stone are better adapted than those made of ordinary stone or metal. In making such rollers or grinders of emery or artificial stone great difficulty has been encountered in consolidating so large a body of granulated stone, flint, or emery when mixed with proper ccment, and when made they are apt to be un equally united, so as to wear unequally and to burst or break away in use. In order to overcome these diiculties and to construct a woodgrinder which should be homogeneous, yet of sufficient size, and which should be efficient y and safe in operation, I devised the grinder for which Letters Patent No. 221,993, dated November 25, 187 9, were granted to me, in which the grinding-cylinder was formed of a number of sections, which were tamped and nished separately, and then conned upon an axle. These sections were in the form of thin disks, which were perforated, and a suiiicient number of them were secured together to form a cylinder of the desired length.

In the present invention the grinding-cylinder, or the` grinding-face of the cylinder, is formedin sections which extend longitudinally of the cylinder, being in the form of logs or staves,instead ofdisks. Theselogs or staves are of artificial stone, and are confined in a proper manner by hoops, bolts, set-screws, clamps, dovetail grooves, or any ordinary or suitable means, upon the surface of a solid or open cylinder, so as to form a proper grinding-surface. The logs or staves may form a single layer around the cylinder, or they may be in several layers. Their shape may be varied more or less; but they should be thin enough in one direction to be thoroughly tamped and consolidated, and of sufficient depth, when se` cured in position on the cylinder, to withstand centrifugal action and the pressure of the wood against their surface. They may be simply placed side by side around the cylinder, or connected with each other by tongue-andjoint or other connection. It is not essential that a cylinder be placed within the sections. They may be secured around the axle, or the interior mounting may be prisinatic.

The following description will enable those skilled in the art to which is appertains to make and use my invention.

Crushed or granulated emcry, corundum, quartz, flint, or any ha-rd stone is formed into a paste or mortar by the use of the proper cementing liquid `or paste, which, being well known, need not be described, and the mass is brought to the proper consistency for molding, tamping, or compressing. The paste or mortar is then castor compressed in a proper mold for the purpose, of different sizes and thickness, as the case may require, into staves or logs, after which it is consolidated under great pressure. When formed, the logs or staves are dried, and usually soaked in some water-proof liquid. The saine are then fully dried and seasoned for use. These logs or staves are confined on the surface of a roll or open-pulley cylinder', forming, when thus placed in position, a perfect cylinder of the proper size, usually from twelve to thirty-six inches in length; but it maybe of such length or size as may be required.

In the accompanying drawings, which form a part oi' this specication, is shown a grinder constructed in accordance with this invention, Figure l being a perspective view, Fig. 2 a longitudinal section, and Fig. 3 a cross-section.

A is the cylinder, composed of the logs or staves a and core b, through the center of which the shaft B passes.

A hoop, C, ordinarily of iron, lits over the ends of the logs or stavesand secures them in position. In order that the hoop may not project beyond the surface of the grinder, the ends of the staves or logs are recessed or shouldered, as shown at c.

The surface ofthe cylinder` A may be plane, corrugated, or of any desired or suitable form.

In using the grinder it may be employed in any ordinary or suitable way. For example, two cylinders, with their surfaces of the proper configuration, constructed in the manner al` IOC sented thereto endwise, diagonally, or side- Io \wise, or as preferred. rlhe grinder, instead of being a true cylinder, may be a cone or other solid of revolution, the proper form depending on the use to Which it is to be put.

The logs or staves need notbe all of the same size, but some may be larger than others.

lV do not, therefore, confine myself to the means described for securing the logs or staves in position, nor to the particular form and dimensions of the saine or of the grinder, nor to any method of grinding Wood 0r other ber by means of said grinder.

Having thus fully described my said invention and the manner in which the same is or may be carried into effect, what I claim, and desire to secure by Letters Patent, is-

l. A cylinder or grinder of artificial stone, einery, or cornndum, for grinding and disintegrating Wood and other ber, having the grinding-surface composed of distinct longitudinal sections, logs, or staves, arranged and held together substantially as described.

2. The combination, with a number of logs or staves of articial stone, einery, or cortindum, of a shaft or arbor and means for confining the said logs or staves thereon, substantially as described.

8. The combination, With a solid or open cylinder, of a number of logs or staves of arti-V cial grinding` material arranged longitudinally on the said cylinder, and hoops or equivalent means for confining said logs or staves, substantially as described.

In testimony whereof I have signed this specification in the presence of t-Wo subscribing Witnesses.

STEPHEN M. ALLEN.

Witnesses:

THOMAS M. GRIDLEY, GEO. A. SAVAGE. 

